Anemia Flashcards
Anemia=
Is a decrease in the RBC count, hemoglobin and or hematocrit values resulting therefore in a lower ability of the blood to carry oxygen to body tissue
*its a sign of a disease process rather than a disease itself
RBCs=
Are flexible biconcave disk, with a very thin membrane which allows gases such as oxygen and co2 to diffuse easily across it
- mature erythrocytes have no nucleus
- immature erythrocytes are called reticulocytes
- life span is 120 days
- RBCs production process named: Erythropoiesis
- the most important hormone for erythropoiesis is ERYTHROPOIETIN (produced in the kidney )
Erythropoietin produced by the kidneys in response to :
Hypoxemia
Mean corpuscular volume (MCV):
-measure of the RBC average size
-allows classification of anemia (normocytic, micro/macrosytic)
-normal range= 80-90fl
MCV=10x HCT(%)/ RBC count
Mean corpuscular hemoglobin concentration (MCHC):
Measure the concentration of Hb in a given volume of packed RBCs
Normal range 32-36 g/dL
MCHC=Hb/HCT
Mean corpuscular hemoglobin:
Mean cell hemoglobin
Average mass of hemoglobin per RBC
MCH= Hb/RBC
Normal range 27-31 pg/cell
WHO grading of anemia:
Grade 1: (mild anemia) 10g/dL
Grade 2/ (moderate anemia) 7-10 g/dL
Grade 3:(severe anemia) below 7g/dL
Classification of anemia on the basis of cause :
1) hypo-proliferative : inadequate production (iron def., b12/folate def., aplastic anemia, anemia of chronic dis., marrow infiltration)
2) hemorrhagic: blood loss
3) hemolytic anemia: increased rbc destruction( immune/non-immune, thalassemia, rbc membrane/ metabolism disorder..)
Classification of anemia on the basis of morphology:
1)microcytic anemia (hypochromic) : MCV & MCH ⬇️ ex. Iron def. / thalassemia
2)normocytic anemia (normochronic):
MCV& MCH normal, ex. Blood loss , hemolytic , chr. Disease
3)macrocytic : MCV& MCH raised , ex. Megaliblastic anemias , hypothyrodism, liver disease and alcoholism , drug toxicity ( phenytoin)
Pathophys. Of anemia:
⬇️ in RBCs, Hb or Hct level
⬇️ O2 carrying capacity
Hypoxia and hypoxia induced effects on organ function
Signs and sympts of anemia
Signs of anemia :
1) pallor of the skin and of the mucos membranes
2) brittle nails
3) koilonychia (spoon shaped nails )
4) papillary atrophy of the tongue
5) angular stomatitis
6) brittle hair
7) dysphagia and glossitis
8) splenomegaly
Diagnosis of anemia:
1) physical examination and medical history ( signs and symptoms of anemia)
2) laboratory tests :
▪️CBC
▪️stool hemoglobin test
▪️peripheral blood smear
▪️iron level
▪️transferrin level
▪️ferritin
▪️vitamin B12
▪️bilirubin
▪️hemoglobin
▪️reticulocyte count
▪️liver / renal function tests
▪️ bone marrow biopsy
Normal values :
Hemoglobin: M(13.5-27.5)/ F(11.5-15.5) Hematocrit: M(40-53%)/ F(36-48%) RBCs: M(4.5-6.5)/ F( 3.9-5.6) MCH: 27-34 pg MCV: 80-95 fL MCHC: 30-35 g/dL Reticulocyte count : 50-150 x10*9/L
Iron deficiency anemia =
-Iron is essential for multiple metabolic processes including O2 transport, DNA synthesis and electron transport
-Iron deficiency anemia is caused by insufficient intake and absorption of iron and or iron loss from bleeding which can originate from a range of sources ( intestinal/ uterine or urinary tract )
🔸 each hemoglobin molecule is made up of 4 heme groups surrounding a globin group, and each heme is containing an Fe atom ( iron atom is attached to a ring-like porphyrin
🔸each heme group binds 1 o2 molecule -> hemoglobin binds 4 o2 molecules
Causes of iron deficiency anemia:
A) low dietary intake
B)increased demands
C) Malabsorption
* most common cause in developed countries is COLON CANCER , also long standing PEPTIC ULCER and bleeds
* most important cause of iron deficiency anemia in developing world children is PARASITIC WORMS
Total body iron mass=
- 5g women
- 5 men
- 80% functional body iron
- 20% iron storage ( hemosiderrin + ferritin)